Hot answers tagged

147

The GIF was sourced from the International Space Station video by astronaut Don Pettit. The video depicts small water droplets orbiting a polyethylene knitting needle which was charged by rubbing it with a piece of paper. Don Petitt states that the blue knitting needles are "8mm in diameter". In the video, Don Pettit clearly says that the attractions are ...


115

Genetic science in Mahabharata Prime Minister Modi claimed that genetic science and plastic surgery existed in Ancient India. source: “We all read about Karna in the Mahabharata. If we think a little more, we realise that the Mahabharata says Karna was not born from his mother’s womb. This means that genetic science was present at that time. That is why ...


105

No. It is a complete invention of an urban myth. Unless anybody produces a Royal Navy document that even does any mention of this influence of Coriolis effect, this seems to be just untrue. A complete fabrication for a good story – good for teaching physics but very bad history. It seems to be an annoying urban myth. The Coriolis effect is present and ...


92

No, it is not true On the Wikipedia page on "Antistatic Device" there were several references to these kinds of things having been examined in a serious manner. ESD Journal It is our opinion that no currently available methods or devices exist which will effectively ground a person without a tethered cord to ground or at least a large capacitance. ...


84

Without acknowledging any of the conditions actually present in the church, wood fires can get much hotter than 600 °C. The maximum temperatures measured within the pile were of the order of 800, 1000, and 1200 °C for piles composed of 1.27, 2.54, and 9.15 cm sticks respectively, although the maximum temperatures for a given size stick appeared, from ...


80

In the television show Penn and Teller Tell A Lie, a competitor to Mythbusters, they conduct an experiment to try this. Here is a YouTube video of the result. In the single instance they show with a slow motion camera, the bullet is indeed at split in half - or at least, fragmented into pieces - by a normal butter-knife. This is not a large sample, and ...


78

It's possible they are actually talking about the rate of energy given off by the Sun that reaches the Earth. However, they are not talking about the amount of energy released, but rather the rate of energy released. The "laser at Magurele, Romania" is actually part of the Extreme Light Infrastructure, a pan-European research project, described ...


66

Yes, GPS requires both general and special relativity to work [Note this is simplified account based on this and this (MS word download)] We can understand why by looking at how GPS actually determines where you are. The system relies on a number of satellites transmitting signals and your GPS device receiving those signals (see wikipedia). There are about ...


65

Mechanical Resonance Certain types of bridge are susceptible to mechanical resonance effects even when marching soldiers are not involved. Mechanical structures usually have one or more frequencies at which some part of the structure oscillates. A tuning fork has a well-defined natural frequency of oscillation. More complex structures may have a dominant ...


56

TL;DR : No, even if one chooses to interpret the excerpt of the Qur'an as such, the maths don't hold up I am going to base this answer on your second source, as the calculation there is reduced to the minimum which makes it a lot easier to show its flaws. This is an answer on the mathematical aspect of the problem, not covering the interpretation of the ...


54

It is indeed a fact, based on the documents released by the FOIA, that both FBI and OSS (the precursor to CIA - CIA didn't exist at that time) obtained papers from Nikola Tesla after his death in 1943. Some of the released material show that the Department of Defense (DoD), among others, was interested in these papers because: "SUBJECT: Papers recovered ...


54

There is Frankin's letter of Oct 1 1752 saying that the kite experiment was performed successfully in Philadelphia, which was read to and published in the Philosophical Transactions of the Royal Society a few months later. There is also Joseph Priestly's The history and present state of electricity (written about 15 years later after discussions with ...


54

Only when the snow is "wet", not if the snow is powdery. As this January 1910 Watson Wagon advertisement says: The popularity of the Watson continues to grow like a snowball rolling down hill on a wet day. This can even happen naturally as explained in the US National Weather Service article Snow Rollers Observed Across Central Illinois (Spring 2003) ...


54

Probably yes: According to at least one expert, the temperature in the Notre Dame fire must have been extremely high, and probably exceeded 600°C. Yesterday the Süddeutsche Zeitung, one of Germany's most reputable newspapers, published an interview with the director of the German Technisches Hilfswerk (the Federal Agency for Technical Relief) and former ...


54

In 1953, a paper looking at some of the factors involved in beer foam answered this question almost as an incidental aside. Jackson, S. (1953). FACTORS AFFECTING BEER FOAM I. CARBON DIOXIDE EVOLUTION. Journal of the Institute of Brewing, 59(4), 317–322. doi:10.1002/j.2050-0416.1953.tb02723.x The main experiments described monitoring the CO2 emissions of ...


47

This is not a lightning strike. It's an underwater blasting explosion Snopes covered this a few days ago. Here's the article. The video was originally posted to YouTube in 2012 to host it for this website. The site says: KÄÄNNY VEDENALAISESSA LOUHINTA- JA RÄJÄYTYSTYÖSSÄ AINA ASIANTUNTIJAN PUOLEEN Rantojen ja vedenalaisen kallion louhinta- ja rakennustyö ...


44

The oldest confirmed use of any version of this quote that I was able to find is from Ray Cummings' short story The Time Professor, published in the Jan. 8, 1921 issue of Argosy All-Story Weekly (thanks to mgkrebbs for pointing this one out): "I do know what time is," Tubby declared. He paused. "Time," he added slowly -- "time is what keeps everything ...


42

The claim that George Biddell Airy wrote a paper titled “On certain Conditions under which Perpetual Motion is possible” which was published in the Transactions of the Cambridge Philosophical Society is true. The full text of the (short) paper can be read on Google Books. The claim that this is a “rigorous mathematical proof of the theoretical possibility ...


40

It's not just your culture. Advice from the US National Weather Service includes: Stay away from windows and doors, and stay off porches. The answer to this related question (including the transcript of interview with meteorologist John Jensenius) and this advice from National Geographic gives some reasons for the advice. Metal frame windows and doors ...


38

Power of the laser This video shows interviews with people at the laser center. At 4:54 you can see the director of the center repeat the claim. In this video, that same director states that the laser was measured at 10.88 PW or 1.088×10^16 W. Remember that watts (W) are the unit of power. The laser does not operate at that power continuously. Just for ...


35

Rudolph Verner, the gunnery officer of the Inflexible, which took part in the battle, wrote a short set of notes about the successes and difficulties encountered during the engagement. He writes Deflection caused considerable difficulty, and on two occasions one gun fired some five or six consecutive rounds nearly a ship's length astern of the target. I ...


34

UPDATE: Funny or Die have admitted that the video is a hoax on their site. Original answer: The "Huvr board" is most probably a hoax product. In addition to Jwenting's answer depicting the problem with the fact that a breakthrough technological achievement wasn't published in any form, professional, scientific or popular. Several sites on the ...


34

I would have to say, yes, it does, but as evidence, one looks not at the scenario described of rolling a snowball down a hill. Instead, in a snowy area, after a significant snowfall and, especially, if it leads to a cancellation of school, go outside and observe children and/or adults building snowmen/women. How do they build the "snowballs" that are the ...


32

Can a man fall faster than the speed of sound? Update (15 Oct 2012): Definitely, yes - 372.8 m/s, or Mach 1.24, Yes, almost certainly, though none have yet (7 Oct 2012) in any well-published verified account. on Aug. 16, 1960, Capt. Kittinger jumped from a height of 102,800 feet, almost 20 miles above the earth. With only the small stabilizing chute ...


31

At this time the Gravitational Constant is regarded as a constant with problematic/low accuracy by physicists. From University of Washington Big G Measurement: Since Cavendish first measured Newton's Gravitational constant 200 years ago, "Big G" remains one of the most elusive constants in physics. The value of big G tells us how much ...


31

Did Manahel Thabet develop a groundbreaking formula to measure distance in space without the use of light? NO! This extraordinary claim which came from Wikipedia: In 2012, Thabet developed a formula that measures distance in space without the use of light.[2] The formula was considered ground breaking in the field of quantum mathematics and is 350 pages ...


30

Words are just that – words. They have no power whatsoever and the laws of physics do not distinguish between "good" words and "bad" words. You speak English, which happens to be one of many thousands of languages that have developed over the centuries. There is no general rule that allows you to categorise "good" words and "bad" words. In some languages ...


30

People have stepped on the Moon when they went there and left footprints, so we've plenty of photographic evidence of their footsteps on the Moon. In fact, it turns out that people do leave footprint in dust, even if they weigh less, like a child leaves footprints on Earth while weighing as much as a man on the Moon. Pictures taken from the Moon itself The ...


Only top voted, non community-wiki answers of a minimum length are eligible